Aneurysmal bone cyst of the capitate: case report and a review emphasizing local recurrence.

We herein report the case of a 15-year-old boy with cystic lesion of the capitate. Magnetic resonance imaging showed that the lesion demonstrated homogenous low-intensity on T1-weighted imaging and homogenous high intensity on T2-weighted imaging. The lesion was treated by curettage and autologous bone-grafting. The histological specimen from the cystic wall showed loose fibrous tissue with capillary vessels and extravasated red blood cells. The cystic lesion was filled with blood, suggesting that the cystic lesion was actually an aneurysmal bone cyst. The present case is the second reported case of aneurysmal bone cyst of the capitate. No recurrence has been observed during the 4 years since operation. We also review the literature related to ABCs of the hand with special emphasis on local recurrence.